Lately, I've been blocked by pretty much any blog that ran the Bad Behavior Wordpress plug-in. It got irritating, so I did some searching, and the only information I could glean is that it blocks any browser it is not aware of.
I'm running Firefox, I said to myself. I thought maybe it was my Ad-Block or NoScript plug-ins, but that wasn't the case.
Then, to make matters worse, I was telecommuting today, and the latest changes someone checked in appeared to break my install at home. Interestingly, I could hit the sites with Internet Exploder, and then it hit me – For fun, I change my UserAgent to have Firefox report itself as "Mozilla Firecrotch".
Apparently, web applications don't have a sense of humor.
After deleting the entry, all is well.
I'm still laughing my ass off over it.